In today's digital audio/visual (A/V) systems, devices of varying types and protocols need to be in communication with a television, such as a digital television (DTV). The data signal paths provided by multiple interfaces between devices of an A/V system can and do vary in protocol and number. For example, a TV or DTV may communicate via multiple data signaling paths to the various modules connected to it, including High Definition Multimedia Interface (HDMI®) CEC, HDMI I2C, HDMI Video, Universal Serial Bus (USB), Ethernet (wired or wireless), IEEE 1394 (so-called Firewire™ or I-link™), Bluetooth, and RF. HDMI®, for instance, is a digital audio/visual connector interface capable of transmitting uncompressed and compressed streams, and can provide an interface between any compatible digital audio/video (A/V) source device, or module, and a compatible digital audio and/or video monitor device, such as a TV. Using HDMI, audio, visual, status and control information may be transmitted via one cable in the system. Consumer Electronic Control (CEC) is a protocol used to control devices that are attached using HDMI. CEC features, as may be defined from time to time in the CEC Specification, include routing control, standby, system information, and feature abort.
A/V devices that operate in accordance with the CEC control protocol are referred to herein as CEC enabled devices, and A/V devices that do not operate in accordance with the CEC control protocol are referred to herein as non-CEC enabled devices. Examples of such A/V device types which may be on a CEC bus connected to a television, in accordance with the CEC specification, include Player, Recorder and Tuner. These devices may communicate with the television via a set-top box (STB) or set-back box (SBB).
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